Impact of IL-8-251A/T gene polymorphism on severity of disease caused by enterovirus 71 infection

The study was performed in EV71-infected patients, with 97 mild cases and 80 severe cases. IL-8251A/T genotypes were determined by the polymerase chain reaction restriction fragment length polymorphism technique. Severe cases had a significantly higher frequency of the IL8-251 AT and TT genotypes than mild cases (52.5 % vs. 49.5 % and 42.5 % vs. 30.9 %, respectively; p = 0.024). The frequency of IL-8-251T alleles among the severe cases was also significantly higher than that of mild cases (68.7 % vs. 55.7 %, OR = 1.8, 95 % CI = 1.1-2.7, p = 0.012). There were significant differences in gender, age, fever days, WBC, CRP and BG concentration, and IL-8 levels among genotypes of IL-8251A/T in EV71-infected patients, but there were no significant differences in ALT, AST, CK-MB and EV71 loads. These findings suggested that the IL-8-251T allele is associated with susceptibility to severe disease in Chinese patients infected with EV71.